Two-phase flow numerical model development based on experimental characterization.

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Two-phase flow numerical model development based on experimental characterization The proposed research program is built to design innovative experiments and develop a theoretical framework for two-phase flows. For industrial applications, the Navier-Stokes equations governing the flows are averaged. This averaging process produces a loss of information on small-scale phenomena. Consequently, modeling these phenomena is required to adequately close numerical models. Our constant concern will be to create experiments to understand and model these small-scale phenomena as the guideline of my research objectives. New developed models will then be implemented in numerical codes based on the averaged Navier-Stokes equations and validated by comparison with large-scale phenomenon experiments. This specific philosophy creates a synergy between numerical and experimental approaches often conducted separately. Three specific objectives support this research vision: a) Model two-phase flow-structure interactions: A first project will study the bubble formation occuring during resin injection for composite manufacturing due to the double scale of the fibre structure. A second project will study the two-phase boundary layer characteristics. Formulating a law of the wall from empirical correlations for two-phase flows would allow numerical predictions at a reasonable cost for complex geometries such as those encountered in the industry and of much better quality than current predictions. b) Determine Particle-particle interactions: A first project will study the phenomenon of coalescence between bubbles inside a two-phase flow, by observing a few bubbles coalescing. The coalescence is part of the balance that governs the bubble sizes and therefore ultimately their trajectories. A second project will measure the turbulence induced by bubbles thanks to innovative technical measurement tools. c) Construct correlation for forces on submerged particles: A first project will numerically assess a bubble rising close to a wall. A second project will study the lift forces of a few particles. If correlations of the force coefficient for isolated particles are relatively well known, their corresponding correlation still requires improvements. A cloud of bubbles placed between a moving bell and a fixed wall will be monitored. A third project will study the drag of a bubble by observing the wake of a rising bubble thanks to 3D PIV. Thus, the research we propose will focus on fundamental experiments to construct an accurate and consistent formulation for dispersed flow simulations. This innovative research will lead to the development of better computational models to shed insight into a variety of two-phase flow problems that affect the welfare of the Canadian population and the competitiveness of the Canadian industry. The lack of reliable two-phase flow numerical procedures prevents breakthrough on the numerous industrial processes using two-phase flow.